Nissan 350z Exhaust Electric Cut Out valve Mod Muffler Bypass On A Switch This mod takes your car from quiet to loud with a flick of a switch. After putting an after market exhaust system on my 350z i was having a look at the old OEM exhaust and i came up with a simple plan to bypass the back box with a small amount of tube and a electric cut out valve. I used a grinder and a dremel to make a hole in the pipe that enters the back box and a hole in one of the pipes that exits the back box which leads to one of the tips. Then i connect the two hole with 2.75 inch pipe. In the middle of this pipe is where i put two flanges to sand wedge the valve in between with two gaskets. I used a basic stick welder to do all of this. The welds were pretty ugly and i wanted to make sure it wouldn't leek at all so i covered the whole thing with brown exhaust past / putty. Later on after the video before i put it back on the car i sprayed it with black heat proof paint, this wasn't necessary i just wanted it to blend in with the underneath of the car for if i ever got pulled over and the police had a quick look at the exhaust. Follow the yellow link to see the exhaust on the road. This mod dose not effect the MPG and got though the MOT, it was tested open and closed.